Question: In the right triangle shown, $BC = 5$ and $AB = 7$. What is $AC$ ? $A$ $C$ $B$ $?$ $5$ $7$
We know $a^2 + b^2 = c^2$ We want to find $b$ ; let $a = 5$ and $c = 7$ So $b^2 = c^2 - a^2 = 7^2 - 5^2 = 24$ Then, $b = \sqrt{24}$ Simplifying the radical gives $b = 2\sqrt{6}.$